Chemists at the University of California, Davis, have engineered blue-green algae to grow chemical precursors for fuels and plastics -- the first step in replacing fossil fuels as raw materials for the chemical industry. "Most chemical feedstocks come from petroleum and natural gas, and we need other sources," said Shota Atsumi, assistant professor of chemistry at UC Davis and lead author on the study published Jan. 7 in the Proceedings of the National Academy of Sciences.